While TRK proteins become constitutively activated or overexpressed when NTRK genes fuse with other partner genes, leading to sustained activation of multiple downstream signaling pathways, including RAS/MAPK and PI3K/AKT, thereby facilitating tumor cell proliferation and metastasis (Figure 3) (Liu et al., 2022; Jiang et al., 2021). This evidence concerns the gene NTRK1 and neoplasm.